function [d2C1yy,d2C21yy,d2C22yy] = d2Cyy(m0,m1,m11,m2,m22,m12,dm0y,dm1y,dm11y,dm2y,dm22y,dm12y,d2m0yy,d2m1yy,d2m11yy,d2m2yy,d2m22yy,d2m12yy)
d2C1yy=(m11*d2m22yy - 2*m12*d2m12yy + m22*d2m11yy - 2*dm12y^2 + 2*dm11y*dm22y)/(m0*(m11*m22 - m12^2) - m2^2*m11 -...
    m1^2*m22 + 2*m1*m2*m12) - ((m11*m22 - m12^2)*(m0*(m11*d2m22yy - 2*m12*d2m12yy + m22*d2m11yy - 2*dm12y^2 +...
    2*dm11y*dm22y) - 2*dm2y^2*m11 - 2*dm1y^2*m22 + (m11*m22 - m12^2)*d2m0yy - m2^2*d2m11yy - m1^2*d2m22yy +...
    2*dm0y*(dm11y*m22 - 2*dm12y*m12 + dm22y*m11) + 4*dm1y*dm2y*m12 + 4*dm1y*dm12y*m2 - 4*dm2y*dm11y*m2 +...
    4*dm2y*dm12y*m1 - 4*dm1y*dm22y*m1 + 2*m1*m2*d2m12yy + 2*m1*m12*d2m2yy - 2*m2*m11*d2m2yy + 2*m2*m12*d2m1yy -...
    2*m1*m22*d2m1yy))/(- m22*m1^2 + 2*m12*m1*m2 - m11*m2^2 + m0*(m11*m22 - m12^2))^2 - (2*(dm11y*m22 - 2*dm12y*m12 +...
    dm22y*m11)*(m0*(dm11y*m22 - 2*dm12y*m12 + dm22y*m11) + dm0y*(m11*m22 - m12^2) - dm11y*m2^2 - dm22y*m1^2 +...
    2*dm1y*m2*m12 + 2*dm2y*m1*m12 - 2*dm2y*m2*m11 + 2*dm12y*m1*m2 - 2*dm1y*m1*m22))/(- m22*m1^2 + 2*m12*m1*m2 -...
    m11*m2^2 + m0*(m11*m22 - m12^2))^2 + (2*(m11*m22 - m12^2)*(m0*(dm11y*m22 - 2*dm12y*m12 + dm22y*m11) +...
    dm0y*(m11*m22 - m12^2) - dm11y*m2^2 - dm22y*m1^2 + 2*dm1y*m2*m12 + 2*dm2y*m1*m12 - 2*dm2y*m2*m11 + 2*dm12y*m1*m2 -...
    2*dm1y*m1*m22)^2)/(- m22*m1^2 + 2*m12*m1*m2 - m11*m2^2 + m0*(m11*m22 - m12^2))^3;
d2C21yy=((m2*m12 - m1*m22)*(m0*(m11*d2m22yy - 2*m12*d2m12yy + m22*d2m11yy - 2*dm12y^2 + 2*dm11y*dm22y) -...
    2*dm2y^2*m11 - 2*dm1y^2*m22 + (m11*m22 - m12^2)*d2m0yy - m2^2*d2m11yy - m1^2*d2m22yy + 2*dm0y*(dm11y*m22 -...
    2*dm12y*m12 + dm22y*m11) + 4*dm1y*dm2y*m12 + 4*dm1y*dm12y*m2 - 4*dm2y*dm11y*m2 + 4*dm2y*dm12y*m1 -...
    4*dm1y*dm22y*m1 + 2*m1*m2*d2m12yy + 2*m1*m12*d2m2yy - 2*m2*m11*d2m2yy + 2*m2*m12*d2m1yy - 2*m1*m22*d2m1yy))/...
    (- m22*m1^2 + 2*m12*m1*m2 - m11*m2^2 + m0*(m11*m22 - m12^2))^2 - (m2*d2m12yy + m12*d2m2yy - m1*d2m22yy -...
    m22*d2m1yy + 2*dm2y*dm12y - 2*dm1y*dm22y)/(m0*(m11*m22 - m12^2) - m2^2*m11 - m1^2*m22 + 2*m1*m2*m12) +...
    (2*(dm2y*m12 + dm12y*m2 - dm1y*m22 - dm22y*m1)*(m0*(dm11y*m22 - 2*dm12y*m12 + dm22y*m11) + dm0y*(m11*m22 -...
    m12^2) - dm11y*m2^2 - dm22y*m1^2 + 2*dm1y*m2*m12 + 2*dm2y*m1*m12 - 2*dm2y*m2*m11 + 2*dm12y*m1*m2 - 2*dm1y*m1*m22))/...
    (- m22*m1^2 + 2*m12*m1*m2 - m11*m2^2 + m0*(m11*m22 - m12^2))^2 - (2*(m2*m12 - m1*m22)*(m0*(dm11y*m22 - 2*dm12y*m12 +...
    dm22y*m11) + dm0y*(m11*m22 - m12^2) - dm11y*m2^2 - dm22y*m1^2 + 2*dm1y*m2*m12 + 2*dm2y*m1*m12 - 2*dm2y*m2*m11 +...
    2*dm12y*m1*m2 - 2*dm1y*m1*m22)^2)/(- m22*m1^2 + 2*m12*m1*m2 - m11*m2^2 + m0*(m11*m22 - m12^2))^3;
d2C22yy=((m1*m12 - m2*m11)*(m0*(m11*d2m22yy - 2*m12*d2m12yy + m22*d2m11yy - 2*dm12y^2 + 2*dm11y*dm22y) -...
    2*dm2y^2*m11 - 2*dm1y^2*m22 + (m11*m22 - m12^2)*d2m0yy - m2^2*d2m11yy - m1^2*d2m22yy + 2*dm0y*(dm11y*m22 -...
    2*dm12y*m12 + dm22y*m11) + 4*dm1y*dm2y*m12 + 4*dm1y*dm12y*m2 - 4*dm2y*dm11y*m2 + 4*dm2y*dm12y*m1 -...
    4*dm1y*dm22y*m1 + 2*m1*m2*d2m12yy + 2*m1*m12*d2m2yy - 2*m2*m11*d2m2yy + 2*m2*m12*d2m1yy - 2*m1*m22*d2m1yy))/...
    (- m22*m1^2 + 2*m12*m1*m2 - m11*m2^2 + m0*(m11*m22 - m12^2))^2 - (m1*d2m12yy - m2*d2m11yy - m11*d2m2yy +...
    m12*d2m1yy + 2*dm1y*dm12y - 2*dm2y*dm11y)/(m0*(m11*m22 - m12^2) - m2^2*m11 - m1^2*m22 + 2*m1*m2*m12) +...
    (2*(dm1y*m12 - dm2y*m11 - dm11y*m2 + dm12y*m1)*(m0*(dm11y*m22 - 2*dm12y*m12 + dm22y*m11) + dm0y*(m11*m22 -...
    m12^2) - dm11y*m2^2 - dm22y*m1^2 + 2*dm1y*m2*m12 + 2*dm2y*m1*m12 - 2*dm2y*m2*m11 + 2*dm12y*m1*m2 - 2*dm1y*m1*m22))...
    /(- m22*m1^2 + 2*m12*m1*m2 - m11*m2^2 + m0*(m11*m22 - m12^2))^2 - (2*(m1*m12 - m2*m11)*(m0*(dm11y*m22 -...
    2*dm12y*m12 + dm22y*m11) + dm0y*(m11*m22 - m12^2) - dm11y*m2^2 - dm22y*m1^2 + 2*dm1y*m2*m12 + 2*dm2y*m1*m12 -...
    2*dm2y*m2*m11 + 2*dm12y*m1*m2 - 2*dm1y*m1*m22)^2)/(- m22*m1^2 + 2*m12*m1*m2 - m11*m2^2 + m0*(m11*m22 - m12^2))^3;
end

